Geomagnetism and Aeronomy

, Volume 58, Issue 6, pp 744–752 | Cite as

The Effect of the Betatron Mechanism on the Dynamics of Superthermal Electron Fluxes within Dipolizations in the Magnetotail

  • A. Yu. Malykhin
  • E. E. GrigorenkoEmail author
  • E. A. KronbergEmail author
  • P. W. Daly


The dynamics of high-energy electron fluxes (with energies over 40 keV) is analyzed in 13 events of magnetic field dipolization observed by the Cluster satellites in the near-tail of the Earth magnetosphere. In all of the events, the observed energetic electron fluxes are enhanced simultaneously with initial dipolization. Good correlation (correlation coefficient >0.6) is observed between the dynamics of the energetic electron fluxes with energies up to 90 keV and the BZ component of the magnetic field. Electron fluxes with higher energies display a decline of correlation with the magnetic field. The increase in electron fluxes with energies up to 90 keV during dipolization development is shown to be mainly due to the mechanism of betatron acceleration. The dynamics of electron fluxes with higher energies is poorly described by the betatron scenario and requires consideration of other, probably nonadiabatic, mechanisms.



E.A. Kronberg and P.W. Daly thank Deutsches Zentrum für Luft und Raumfahrt (DLR), project no. 50 OC 1602, for support of the RAPID device.


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Copyright information

© Pleiades Publishing, Ltd. 2018

Authors and Affiliations

  1. 1.Space Research Institute of the Russian Academy of SciencesMoscowRussia
  2. 2.Max Planck Institute for Solar System ResearchGöttingenGermany
  3. 3.Ludwig Maximilian University of MunichMunichGermany

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